Great Britain was neutral Switzerland's main supplier of heavy weaponry during the early Cold War. The author analyzes this armaments relationship against the background of Anglo-Swiss relations between 1945 and 1958, and thereby assesses the role of arms transfers, neutrality and Britain, as well as the two countries' political, economic and military relations. By using multi-archival research, the author discovers "traits of specialness" in the Anglo-Swiss relationship, analyzes the incentives for Berne's weapons purchases and London's arms sales, sheds new light on the Cold War arms transfer system and the motivations of the participating states, and questions the sustainability of neutrality during the East-West conflict, as well as Britain's role from a western neutral and small power perspective.